The invention relates to a spinning machine having a plurality of adjacently arranged spinning units, each containing a sliver feeding device for the withdrawal of a sliver from a container and for the introduction of the sliver into the respective spinning unit. Devices are provided for picking up the starting portion of a new sliver of a readied container and for connecting it with the old sliver entering into the respective spinning unit. Devices are also provided for stopping the sliver feeding device in order to leave an end portion of the old sliver which remains outside the spinning unit to be connected with the new sliver.
Reference is also made to our application Ser. No. 07/302,411, filed on Jan. 27, 1989, titled A SLIVER SPINNING ARRANGEMENT FOR SPINNING MACHINES and based on German Application No. P 38 02 413.6 filed on Jan. 28, 1988 in the Federal Republic of Germany.
In the case of a known spinning machine of the initially mentioned type (DE-A No. 35 01 875), it is provided that either the connecting of the end portion of the old sliver with the starting portion of the new sliver takes place such that approximately the same number of fibers exist in the connecting point, or that, before a silver piecing or connection, the fiber feeding device first remains switched on until the connection point between the slivers has entered into the spinning point, the fibers which are fed to the spinning point not being used for the spinning process but being removed as waste.
It is also known (DE-C Nos. 25 36 435 and 26 46 313) to first completely use up the sliver in the respective spinning units and then, as a result, generate a signal by means of which a following is triggered of a container with a new sliver and, if necessary, an automatic threading of the starting portion of the new sliver into the respective spinning unit.
It is also known (DD-PS No. 107 952) to feed the sliver to a fine-spinning machine in large containers which, at the fine-spinning machine, are transferred to smaller containers circulating on a conveying device. The sliver will then enter into the spinning units from the smaller containers. Two of these smaller spinning cans are assigned to each spinning unit, these spinning cans being arranged above one another. The end portion of the sliver of the just-serviced spinning can is connected with the starting portion of the sliver of the spinning can that is located in the supply position or is brought into the supply position, so that a continuous feeding of the sliver is possible.
In the case of drafting units with automatic conveying systems (EP-A No. 0069 087), it is known to grip a starting portion of a sliver hanging down over the edge of a container by means of gripping elements which contain suction devices or pairs of clamping rollers.
It is also known (EP-A No. 0212 979) to arrange an automatic can changing device between two drafting units or frames which is also connected with an automatic device for the joining of the slivers. The filled cans, which leave the first drafting unit, arrive at a revolving table on which they are revolved slowly. The sliver starting portion hanging down over the can edges is then taken off by a suction gripper equipped with a sliver detector which passes this starting portion on to a transfer device which then places the starting portion of this sliver in the intake elements of the second drafting unit.
An object of the invention is to further develop an arrangement of the initially mentioned type by bringing the starting portion of the new sliver into a position in which it can be easily connected with the end portion of the old sliver.
This object is achieved according to the invention in that the devices for picking up the starting portion of the new sliver of the spinning unit and of the end portion of the old sliver remaining outside this spinning unit can be applied such that the end portion of the old sliver and the starting portion of the new sliver overlap one another.
By producing an overlapping of the end portion of the old sliver and the starting portion of the new sliver, a connection can easily be established between the two slivers.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.